Guest Count at Home Event - in-laws overlooking safety?

Help! Indian-western fusion wedding in May 2023 - Indian in-laws want to host a pre-wedding party at home, the night before the ceremony which is also at home. Our wedding planner has said we could comfortably fit no more than 80 people in the indoor-outdoor space if we covered the pool, so that’s the count we’re planning ceremony around. They have been reluctant to listen to our wedding planner for other wedding decisions, and I feel like they don’t believe her digital floor plan and years of experience is correct.


The pre-wedding party the night before - when we started planning back in Summer 2022, the 4 of us had agreed around 100 guests invited, some of which were courtesy invites so we anticipated around 80. Now that they’ve actually started writing down names of guests, they’re at 150 guests, are struggling to reduce that count down, and seem to think 150 guests would be fine in the house/backyard. I disagree, mainly for safety reasons but also for my own sanity. I worry about damage to the house, parking (valet needed), cleanliness of the bathrooms etc., cleanup in between events (early start next day for ceremony)… and the fact that our wedding planner has said 80 people safely. We’re trying hard to persuade them that it would be better to host the party at a separate venue, but they are convinced that it would be fine to host at home and that the cost of a separate venue would far outweigh any costs incurred to host an event at home.
Thoughts, advice, any ideas welcome - I’m at a point where if this party is held at the house then I don’t think I want to be there… at our own wedding events!